High prevalence of vitamin D and calcium deficiency among pregnant women and their newborns in Chengdu, China

Abstract

Background: Vitamin D and calcium deficiency is common in pregnant women and newborn infants. There are few data about the prevalence of hypovitaminosis D during pregnancy and infancy in China. We assessed vitamin D status of pregnant women and their neonates in Chengdu, Sichuan province, China.

Methods: Maternal serum and cord blood levels of calcium, 25-hydroxyvitamin D [25(OH)D], alkaline phosphatase, and parathyroid hormone (PTH) were studied in 77 urban and rural mother-neonate pairs at term.

Results: The mean level of maternal serum 25(OH)D was 35.95+/-19.7 nmol/L, and that of cord blood 25(OH)D was 40.98+/-18.89 nmol/L. The intake of calcium and vitamin D was uniformly low, although it was higher in urban (1010+/-450 mg/d, 237+/-169 IU/d) than in rural (320+/-210 mg/d, 62+/-66 IU/d) women. Maternal serum 25(OH)D was correlated positively with cord blood 25(OH)D (r=0.94, P<0.01).

Conclusions: There is a high prevalence of vitamin D and calcium insufficiency in pregnant women and neonates in Chengdu even when mothers are compliant with prenatal vitamin supplementation. Supplementation is needed to improve maternal and neonatal vitamin D and calcium nutrition.